Iterative Quadrature Demodulation for Harmonic Synchrophasor Estimation

With the increasing usage of power electronic devices that contribute to harmonic distortion in power systems, analysis of harmonic components has become important for maintaining power quality. Moreover, time-synchronized point-on-wave measurements are of growing interest for analyzing dynamic phenomena in power systems, where synchrophasors that report a magnitude and angle of the estimated fundamental component of a signal are insufficient. This paper proposes a new method for estimating harmonic content by applying quadrature demodulation iteratively to estimate a synchrophasor for each harmonic component of a power system signal. We first apply the method to simulated signals to verify its accuracy, then we demonstrate its effectiveness at reconstructing a signal from data measured from real power distribution systems.